Basically the fish oil is very good for human health and most of the times it is used by the people as the food supplement. But there are some fish oil side effects which are happening because of some reasons such as the pollution of water which allows the chemicals to enter the body of the fish and the oil we consume also contains the same chemicals and so it affects. The other reason is that the oil spilled in the water and this oil enters the body of fish and so later on this shows side effects on human body